So when I go for a while between fill ups, when I open the fuel cap, it depressurizes quite a bit. I know this is quite common, but heres the thing. I was decelerating down a pretty large hill, car said it was ~1/4 tank on flat ground, yet i ended up fuel starving and the car died. Hit level ground, car restarted, no biggie, fill up time. Pulled up to a pump and left the car running. Unscrewed the cap and it depressurized quite a bit, and when the pressure ran out, the car sputtered and died! Im pretty sure thats not a good thing, and im worried that the pressure is giving me false readings. also im unsure on how the pressure could keep the engine going, minus maybe somehow forcing fuel into the pump. Either way, this seems like an issue as i thought the tank was supposed to have a pressure vent to preVENT this sort of thing from happening.

 

Did you ever figure it out? I am having kind of the same issue.

 

when the in tank pump gets old and weak. the built up pressure sorta helps it along.you should think of replacing it at this point

 

Thanks for the input...I pretty much figured that the pump was my problem. I have had a pump for about a month but have changed them before and it is quite a time consuming process. I am really considering cutting a hole above the tank and building a door for future changes. probably will tackle it this weekend.

 

NOOOOOOOO!!! don't cut a door,please .these cars deserve much better than that

 

From what I've heard, the pressure in the tank actually helps the pump in the tank push fuel. If you don't have any pressure, the pump struggles to move fuel. So when you depressurized the system, it's possible that you starved the engine and that's why it died. My fuel gague jumps around all the time, I think it's just how these cars are.

 

not exactly, while its true that they will only show the actual amount of fuel when parked on a level surface. if your fuel gauge "jumps around". you have a bad gauge or sending unit.

 

I guess jump around was a bad way to put it. Going down hill it tells me I have no fuel, going up hill it says I have lots (IIRC), potentially the opposite.

 

I would run some tests on that ,pronto. to me, a car without a reliable fuel gauge might as well not even have an engine.

 

Please don't run the car when you pull the gas cap. That is not air coming out but a highly flammable fuel air mix. Should it reach the hot exhaust or the wind carry it to the engine or dash or the jerk with the cell phone, an explosion is quite possible. It is much more flammable than the liquid gasoline. We don't need to lose another 3rd gen Camaro!